The present invention is related to the structure of a drilling machine convenient for changing its drill bit, and for fast adjustment of the desired depth of drilling, and especially to the structure suiting a drilling machine or the like.
Conventional drilling machines generally are provided with clamping portions for changing drill bits, and the desired depths of drilling are all decided following the feeling of operators, if the holes drilled are too shallow, many times of repeated drilling are required; and either case that the holes drilled are too deep or the workpieces are pierced is not desired.
In order to get rid of the defects in drilling, another structure of drilling machine has been disclosed, such as the xe2x80x9cREMOVABLE DEPTH GUIDE FOR ROTARY CUTTING TOOLxe2x80x9d of the U.S. Pat. No. 5,829,931 (as shown in FIG. 7); the drilling machine 10 of such structure has a clamping portion 18 for the bit with an axle collar 22 over it. The axle collar 22 has an extended arm 22a extending outwardly therefrom and provided with a screw hole. An abutment seat 24 with a similar shape as that of the axle collar 22 is stacked with an extended arm 24a thereof on the extended arm 22a of the axle collar 22. The extended arm 24a is provided thereon with an elongate slot, a screw 28 is extended through the elongate slot and the screw hole respectively of the extended arm 24a and the extended arm 22a; by screwing off or on of the screw 28, the height of the abutment seat 24 can be adjusted to get the object of having a suitable drilling depth. However, in practice, the drilling machine has the following defects:
1. The axle collar is fixedly provided on the clamping portion of the drilling machine, it is inconvenient in changing the bit.
2. The axle collar is fixed to the abutment seat by means of a screw, screwing off or on of the screw is easy, however, it can not get the object of fast adjustment, and thereby is not desired.
In view of the defects of the conventional drilling machines, the inventor of the present invention studied and developed the present invention based on his professional knowledge and practical experience of years in designing and marketing of the related products, in order to provide convenience in use for the consumers, and this is the motive of the present invention.
The primary object of the present invention is to provide a structure of drilling machine, by providing a control rod on an adjusting and fixing seat, a desired height of the adjusting and fixing seat can be fast acquired.
The secondary object of the present invention is to provide a structure of drilling machine having an adjusting and fixing seat which can be fast assembled and detached.
To get the stated objects, the present invention is provided with a main machine of the drilling machine, the main machine is provided on one end thereof with a control switch. By pressing the control switch to position the clamping portion for a bit, the bit can be changed conveniently, and the adjusting and fixing seat can be fast connected to the periphery of the clamping portion. The adjusting and fixing seat includes a fixing seat and an adjusting rack to be stacked with each other by means of the vertical walls respectively provided on the peripheries of the two, and a latching bolt and a control piece are pivotally connected to the vertical walls. By pressing the control piece, the adjusting rack can be fast adjusted for its desired height, so that the bit can be used to drill a hole of a desired depth.
The present invention will be apparent in its particular structure and characteristics after reading the detailed description of the preferred embodiment thereof in reference to the accompanying drawings.